// Copyright (c) 2017-2026, University of Cincinnati, developed by Henry Schreiner

// under NSF AWARD 1414736 and by the respective contributors.

// All rights reserved.

//

// SPDX-License-Identifier: BSD-3-Clause

#include <CLI/CLI.hpp>

#include <ctime>

#include <iomanip>

#include <iostream>

#include <sstream>

#include <string>

// Custom validator is an alias of Validator, the constructor takes a function that takes as input and returns a string

const CLI::CustomValidator ISO8601(

[](std::string &input) {

std::tm tm = {};

std::istringstream ss(input);

ss >> std::get_time(&tm, "%Y-%m-%dT%H:%M:%S");

if(ss.fail()) {

return std::string("Failed to parse time string");

}

return std::string{};

},

"datetime[%Y-%m-%dT%H:%M:%S]");

int main(int argc, char **argv) {

CLI::App app("custom validator testing");

std::string value;

app.add_option("--time", value, "enter a date in iso8601 format")->check(ISO8601)->required();

CLI11_PARSE(app, argc, argv);

std::cout << "date given = " << value << '\n';

return 0;

}